Re:Reworking 30 lines of Linux code could cut power use by u...
by Denvercoder9 on Tuesday April 22, 2025 @02:47AM
(#43759640)
The article is terrible, this doesn't affect the default NAPI behaviour. See the LWN link posted elsewhere for a more detailed, technical discussion. From the patch set itself:
> If this [new] parameter is set to a non-zero value and a user application
has enabled preferred busy poll on a busy poll context (via the
EPIOCSPARAMS ioctl introduced in commit 18e2bf0edf4d ("eventpoll: Add
epoll ioctl for epoll_params")), then application calls to epoll_wait
for that context will cause device IRQs and softirq processing to be
suspended as long as epoll_wait successfully retrieves data from the
NAPI. Each time data is retrieved, the irq_suspend_timeout is deferred.
> If this [new] parameter is set to a non-zero value and a user application has enabled preferred busy poll on a busy poll context (via the EPIOCSPARAMS ioctl introduced in commit 18e2bf0edf4d ("eventpoll: Add epoll ioctl for epoll_params")), then application calls to epoll_wait for that context will cause device IRQs and softirq processing to be suspended as long as epoll_wait successfully retrieves data from the NAPI. Each time data is retrieved, the irq_suspend_timeout is deferred.